EULESS (CBS 11 NEWS) – Copper thieves are creating more than a nuisance for the Hurst-Euless-Bedford Independent School District.

Four times since the first of the year thieves have climbed onto the roof of elementary schools to steal copper drain pipes.

“It is very frustrating because school districts are strapped,” says Judy Ramos, the district’s communications director.

She tells CBS 11 News that four HEB schools have been targeted in three different cities since the first of the year. One in Hurst, one in Bedford, and two in Euless.

“They seem to be coming at night,” she says of the thieves, “and they’re taking copper pipe that are part of the air conditioning units that are on top of the roofs.”

South Euless Elementary was hit over the weekend; North Euless Elementary on January 3rd. In both cases police tell us the thieves got 300-feet or more of 3/4″ copper pipe used to drain water away from AC units.

Bell Manor Elementary in Bedford was targeted earlier this month. And Harrison Lane Elementary in Hurst was hit January 25th.

“There are no leads on this case,” says Hurst Police Lieutenant Mark Schwobel, who adds copper thefts of all kinds are reported weekly.

“Apartment complexes come in to find their air conditioning cores have been removed, behind businesses and strip centers it’s common.”

Ramos says school maintenance crews haven’t let the thefts affect kids in the classroom. Parents are grateful for that…even if they’re frustrated that their schools are the targets of thieves.

Dhera Allison’s sixth grader attends South Elementary and laments, “There’s not really more we can do about is as individuals. They’ll (the thieves) get their payback later in life, I guess.”

Because of storm and hail damage in 2011, copper pipe is being replaced with modern C-PVC tubing at schools throughout the district. But the old pipe is still valuable.

The district has filed insurance claims but says the financial impact on all this isn’t known just yet. Ramos has a message for the thieves. “They’re stealing. They’re stealing from the children of this district and they’re stealing from the taxpayers.”